This invention relates to a composition and to a method for administering a drug or other beneficial chemical compound topically to the body. More especially, the invention concerns composition and a method for enhancing dermatological or percutaneous absorption of such active agents in compositions for the use of humans and domestic animals.
It is well known that the outer or surface division of the epidermis, known as the stratum corneum or horny layer of the skin, acts as a barrier to penetration of external substances into the immediate area as well as into the body. Often times, however, it is desired to increase the degree of dermatological or percutaneous absorption or penetration of a particular therapeutically active dermal preparation, as for example in the treatment of skin disorders, subcutaneous infections, cosmetic effects, or the like.
In this regard, several reagents and methods for increasing the permeability of the skin have been disclosed in the art. For example, occlusion of the skin with metal guards, plastics, or other wraps has been employed to increase the penetration of various agents into the epidermis. Similarly, an increased rate of absorption into the skin has been produced by adjusting the temperature of the skin and/or by regulating the temperature and relative humidity of the adjacent atmosphere. Most effective, however, have been the recent efforts directed toward the discovery and application of chemical absorption promoters which are employed as integral components of therapeutically active or bioaffecting compositions. Workers in this area have experienced varying degrees of success in their endeavors to locate truly effective topical or percutaneous absorption promoters, since a great number of chemical compounds have been found to promote absorption, at least to a degree, as for example in British Pat. No. 1,001,949 and U.S. Pat. No. 3,472,931.